Right now, if a tall coffee has a list price of $1.60, the company will sell it to me for $1.50 if I bring my mug. Instead, it should set the price at $1.50 and charge 10 cents extra for the paper cup…

People tend to work harder to avoid losses (the 10-cent charge for a paper cup) than they do to pursue gains (the 10 cent discount for bringing your mug).